Feeding daphnia

What I discovered works very well for feeding daphnia in the winter, beyond the soy wheat/yeast/sugar mix is to take pure spirulina flake, maybe about a small handful of it, and place it in blender with about a cup of so of water from one of the fish tanks (dapnia don't do well at all with freshly treated or tap water). Blend the snot out of it until it is a spirulina slurry with no visible flakes left, essentially a poor man's version of greenwater. I pour this in with the daphnia and their population explodes. Sometimes I mix a little bit (maybe a pinch) of the soy wheat/yeast/sugar mix in with the slurry as well for a boost. I can't say I've notice a difference with or without that mix, but it doesn't seem to hurt.

OK. You guys have talked me into giving this a try. Never raised daphnia before. Are they tricky at all?

dnrdarryl wrote:

OK. You guys have talked me into giving this a try. Never raised daphnia before. Are they tricky at all?

I had several cultures crash on me until this last batch which I got from Tom Gromek last spring. They've done very well for me, I feed daphnia to assorted fish at least once a week, I've given away starter cultures and I sold several at the last auction. There are many recipes for feeding daphnia, but the trick seems to be not to overfeed. Feed them once and do not feed again until the water is clear.

What has been working for me is treating them like fish. Use treated water, don't overfeed and do at least a 25% water change once a week. Dani's spirulina food works great but requires a blender which has to be washed. The soy mixture is 1 cup soy flour, a tsp of sugar and a pinch of yeast. I just shake up a pinch in a small covered bowl and feed the daphnia every few days (and rinse the bowl in the daphnia tank ). I think Tom just uses the soy flour.

I keep two 5 gallon buckets of daphnia plus a small container as a back up in case of a crash. You can also add a snail or two, and Tom says he currently has some blackworms in his.

Light seems to make a difference - mine are reproducing more quickly with more light. Dani says she keeps a light on hers all the time. I just use about 18 hours with a 60 watt bulb hanging above the buckets.

They do well outdoors in the summer, and mine survived all the heat last year.

Good luck! Just remember not to put all your eggs in one basket - keep at least two containers going.

Sue

Sounds doable. Thanks Sue and Dani.

Do you have a filter in the dapnia tubs?

Nope, I just have a slow flow of air into my tub, but I don't think most other people do it this way. I would think a filter of any type would just catch more daphnia in it and clog up. They're not very strong swimmers.

How long do you typically go between feedings Sue? Can I be gone for 10 days and not have them fed?

I used an airstone the first couple of times, but don't use one with this batch. And you were right about the light being more important than the temperature.

I feed mine about every third day, but basically I go by how the buckets looks. When the water is clear I feed them again. I could probably feed more less often but I would worry about crashes, Don't know about leaving them that long. I would think they would starve unless they were outside and their container was producing green water or something.

Sue